Check-valve mechanism.



G. P. CARROLL & F. N. RO EHRICH.

CHECK VALVE MECHANISM.

APPLICATION FILED JULY 5. 1911.

1 1 84,4 1 8. Patented- May 23, 1916.

2 SHEETS-SHEET I.

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G. P. CARROLL & F. N. ROEHRICH.

CHECK VALVE MECHANISM.

APPUCATION FILED IULY5. 19H.

Patented May 23,1916.

2 SHEETSSHEET 2.

mmwto m GEORGE P. CARROLL, 0F HARTFORD, CONNECTICUT, AND FRANK N. ROEHRIGI-I, OF JERSEY CITY, NEW JERSEY; SAID ROEHRICH ASSIGNOR TO SAID CARROLL.

CHECK-VALVE MECHANISM.

TocaZl whom it may concern:

Be it known that We, GE RGE P. CARROLL and F RANK N. Ronrinion, citizens. of the United States, residing, respectively, at the city of Hartford, county of Hartford, and State of Connecticut, and 'at the city of J ersey City, county of Hudson, and State of Newdersey, have jointly invented a new and useful Check-Valve Mechanism, of which the following is a specification.

Our invention relates to improvements in the means for actuating check valves, especially wheresuch valves are used to control the outflow of heated ammonia gas from thestills of automatic intermittent absorption refrigerating machines.

The especial purpose of our invention is to provide mechanism whereby such a valve may be unlocked simultaneously with a starting of the heating of the still, so that the valve may open as soon as the pressure of the gas expelled from the solution of aqua ammonia in the still begins to. increase; whereby such a valve may be closed evenly and without strain as soonas any such heating terminates; wherebysuch a valve may open as a. safety valve in case abnormal conditions of pressure arise in the still during such periods as the valve should normally be closed; whereby the movements of the valve mayresult from lesser movements of an imperforate diaphragm forming a part of the valve chamber walls; whereby the lodgment of scale between the valve and its seat may be prevented; and whereby all the parts withinthe valve chamber walls may be readily accessible.

Our invention includes means for accom- .plishing these various purposes.

,the minor parts inplan view.

The'means employed to these ends are as will appear. There are alsoimproved details of construction aswill appear.

In the drawings, Figure l is afront end .elevationof ourinvention. Fig. 2 is a vertical section through the line 2-2 of Fig. 1, looking toward the right and with some of the minor parts in elevation. Fig. 3 is a partial front elevation and a partial ver- ,tical section throughthe line 3-3 of Fig. 2, looking toward the left and with some of the minor parts in elevation. Fig. 4 is a horizontal section through the line H of Fig. 2, looking downward and with some of Fig. 5 is a left side elevation of a lever end and certain Specification of Letters Patent.

. WVithin the passage 3 is a check valve 5 having an annular Patented May 28, 1916. Serial No. 636,917.

adjacent parts. Fig. 6 is a partial plan view figure. A casing 1 has a vertical inlet passage 2,

extending from the lower end of the casing upward and then to the left, as seen in Fig.

2, and a vertical outlet passage 3, connecting in front with the passage 2 and extending up through the top of the casing. In an annular groove in the casing 1 around the space where the passage 2 leads backward into the passage 3, is a ring shaped valve seat 4, which preferably is made of lead or of an alloy of lead and tin. The passage 3 has its beginning in the casing I quite a little distance below the seat 1.

on the seat 4 and having on its side opposite to the rim a semi-spherical boss. In the valve 5, axially coincident with its rim, there is a cylindrical threaded recess with a semispherical socket at its inner end extending into the boss of the valve. A valve stem 6 has a spherical head, occupying the socket of the valve 5; has, next to its head, a back cylindrical section; has, for about two fifths of its length and in front of this back section, a central cylindrical section, of reduced diameter and threaded around its front part; and has a front cylindrical section of a diameter still further reduced. A slotted and externally threaded ring 7, just large enough .to be slid over the back cylindrical section of the stem 6, is screwed into the cylindrical recess of the valve 5 and has within its end a partially spherical recess, fitting over and securing the spherical head of the stem. The back section of the stem 6 reciprocates in an opening through a transverse, horizontal bracket 8, integral with the casing 1. urrounding the central section of the stem 6 is a flanged sleeve 9, adapted to reciprocate slightly on the stem.

l/Vithin the passage 2 is a vertical lever 10, forked at each end and having a pivot opening nearest to the fork of its lower end. The upper fork of the lever 10 is of more than semi-cylindrica1 form, as viewed from left to right and the reverse, and its arms respectively occupy a more than semi-cylindrical recess in a right slide block 11 and in a left slide block 12, these recesses opening downward from their respective blocks. The blocks 11 and 12 are respectively on the right rim adapted for seatingand left sides of the sleeve 9, within its flanges, and slightly slide up and down as the lever 10 is rotated. On the inside of the left part of the wall of the casing 1 inclosing the passage 2 is a pivot recess 13 and still nearer the passage and axially coincident with the pivot recess is an annular recess containing a spacing ring 145. Passing through and occupying a threaded opening in the right Wall of the casing 1, opposite to and axially coincident with the pivot recess 13, passing through the pivot opening in the lever 10, passing through the ring 14: and occupying the recess 13, is a pivot 15, having to the right of the lever a shoulder enlargement so that, while the lever is free to rotate on the pivot, it is kept from shifting along the pivot by this enlargement and the ring. The right end of the enlargement'of the pivot 15 is threaded, to correspond with the threads of the opening in the right wall of the casing l; the extreme right end of the pivot formsa nut; and between the threaded part and the nut part of the pivot is an annular ring integral with the pivot. In an annular recess around the outside of this threaded opening in the casing 1 is a gasket 16, so that when the pivot 15 is screwed into place by its nut the gasket is compressed and a gas tight joint results.

Surrounding the central section of the stem 6, in front of the sleeve 9, is a relatively heavy helical compression spring 17; and screwed around the threaded part of this central section is a slotted ring 18, so longitudinally adjusted as to bear lightly on the spring 17 when the sleeve 9 is in its extreme back position. The upper front part of the casing 1 has an internally threaded opening, connecting with the passage 2 and axially coincident with the seat 4:; and it has around this opening an annular groove, containing a gasket 19. A hexagonal front cap 20 is adapted for screwing into this upper front opening in the casing 1 and has an annular tongue for compressing the gasket 19. The inside of the cap 20 is deeply recessed and, near the longitudinal center of the cap, this recess is threaded. A ring 21 is screwed into the threaded part of the recess of the cap 20 and has an opening axially coincident with the seat 4 and adapted to permit of the reciprocation of the front end of the stem 6. A relatively light helical compression spring 22 surrounds the stem 6 in front of the ring 18 and has its front end resting in an annular seat in the ring 21. Thus the spring 22 is always held under tension by the rings 18 and 21 after the cap 20 has been screwed into place. The springs 17 and 22 are preferably of the kind known as nickel springs.

The lower front part of the casing 1 has an opening connecting with the passage 2, threaded for most of its length and forming thimble 26.

at its inner end a seat for an annular gasket 23. Into a threaded recess in the wall at the back part of the casing 1 and axially coincident with the lower front opening in the wall of the casing, is screwed the back end of a cylindrical rod 24:, which is held in place by a lock nut 25 bearing upon-the back wall of the casing. The parts are so positioned that the rod 24 is within the space between the arms of the fork at the lower end of the lever 10, without, however, impeding the rotation of the lever. A flanged thimble 26 loosely surrounds the rod 24:, has its flanged part in front of the front end of the rod and has its back annular part bearing against the front of the lower fork of the lever 10. A flexible diaphragm 27, preferably of nickel, fits over the gasket 23 and bears upon the flanged part of the A thrusting member 28 has a T-like head bearing upon the central front of the diaphragm 27 and has a stem extending frontward. The front face of the stem of the member 28 is inclined so as to slope slightly backward, the lower edge being in advance. A front cap 29 has a central opening loosely surrounding the stem of the member 28 and has a back annular recess serving as a guide for the T-like head of the member. The cap 29 is screwed into place, so as to compress the diaphragm 27 upon the gasket 23 by inserting a spanner into tWo holes 30, near opposite edges of the outside of the cap.

The lower outside end of the casing 1 is threaded and around the inlet end of the passage 2 is an annular recess containing a gasket 31. A flanged pipe end 32 fits into the lower end of the casing 1 against the gasket 31 and has its flange below the casing. A cup coupling 33, slid over the pipe end 32 from beneath, screws around the threaded lower end of the casing 1 and with its perforated end partition bears against the flanged part of the pipe end so as to compressthe gasket 31. The coupling 33 is in the form of a hexagonal nut at its lower end, but has a recess running entirely around its upper end. In the back part of the recess of the coupling 33 is a half collar 3%. An up wardly extending bracket 35 has integral with its lower end a half collar resting in the recess ofthe coupling 33 and clamped to the half collar 34 by bolts 36, so that the p position of the bracket is rigidly maintained. The upper half of the bracket 35 is in the form of two-upright parallel supports upholding a lower cross piece 37 and an upper cross piece 38. Each cross piece 37 and 38 has a vertical rectangular recess, the two recesses being in alinement with each other. A lower strip 39 is secured by screws 40 to the opposite end of the cross piece 37 so as to inclose its recess in front. An upper strip I A1 is secured by screws 42 to the opposite .part of the of the member being parallel.

Back of the seat 4 the casing 1 has an internally threaded opening, .connecting with the passage 3 and axially coincident with the seat; and it has around this opening an annular groove, containing a gasket 44. A hexagonal back cap 45' is adapted forscrewing into this back opening in the casing 1 and has an annular tongue for compressing the gasket 44. The upper outside end of the casing 1 is threaded and aroundwthe outside end of the passage 3 is an. annular recess containing a gasket 46. A flanged pipe end 47 fits into the upper end of the casing 1 against the gasket 46 and has its flange above the casing. -A cup coupling 48, in the form of a hexagonal nut around. its upper end and slid over the p ipeend 47 from above, screws around. the threaded upper end of the casing 1 and with itsperforated endpartitionbears against the flanged pipe end so as to compress. the gasket 46. r 1 1 It is assumed that the pipe. end? 32 leads from the top of the. aqua ammonia still of an automatically operated intermittent absorption refrigerating machine; that the pipe end. 47 leads to an ammonia gas condenser; and that the rod 43 is automatically moved'upward-when the heating of the still begins and downward when the. heatingof the still terminates.v

The method of operationlis as follows: Assume all parts to be in the positions shown in the drawings. .With. anupward movement of the rod 43, which may be rather quick, the member 28 is relieved and is free to move frontward as the thrusting face of the rod slides upward. along the face of the member. Consequently the pressures of the diaphragm 27 upon the thimble 26 and of the thimble upon the lower fork of the lever 10 arealso relieved. Thereupon the spring 22, acting according to its tendency, thrusts the ring 18 and the'stem 6 backward so as to at once open the valve 5, unless, indeed, thegas pressure on the outside of the valve exceedsor equals the combined forces of the gas pressure on the inside of the valve and of-the spring. The

spring 22, it should be remarked,is of suf-' ficient force to just overcome the inertia of the moving parts, as herein described, other than the rod 43. Of course, if the gas pressure on the outsideof thevalve 5 is high,

the opening of the valve isdelayeda little,v

until, in consequence of the heating of the aquacammonia in the Still, the gaspressure on the inside of the valve, reinforced by the spring 22, opensthe valve. But such delay lS-Of no consequence. With the relief of pressureon the lower fork of;the lever 10,

the spring 17 thrusts the sleeve?) a little backward along the central section of the .stem 6. And in relation to the pivot 15, the

backward movement of the sleeve 9 is much increased by the actionof the spring 22 in moving backwardzthe ring .18 and the stem 6,.whenever such latter movement occurs. With. aback movement of'ihe sleeve 9,:the blocks 11 and 12 first slide slightly upand then downso as to rotate backwardithe upper fork of the lever '10. This back rotation ofthe upper fork offthe lever 10 rotates frontward the lower fork of the lever so as to movefrontward the thimble 26 along the rod 24. The frontward movement of the thimble 26 moves outward the diaphragm 27 and the member 28, the front face of the member being now. incontact with the lower part ofthe thrusting face of the rod 43. The valve 5 is now open and 'all the moving parts remain in :the positions indicated while the valve is'open.

Witha downwardmovement of the rod 43, which also may be rather quick, the face ofthe rod bears-upon the face of the member 28 so as to thrust the member,- the dia- 'phragm 27 q and the thimble 26 inward and backwarduntil the flanged part of the thimble nearly or quite comes into contact with the front end of the rod 24. There- .upon the thimble 26 forces the lower fork of the lever 10 backward and the upper fork forward; this upper fork'moves the slide blocks 11 and 12 slightly up and down; and the slide blocks force the sleeve-9 forward. The forward movement. of the sleeve :9tends to compress the spring 17 so as to move it: a little way along the stem 6; but

the main effect of such forward movement is exerted, through the spring 17, upon the ring 18, compressing the spring 22 and forcing forward the ring 18, the stem 6 and the ring 7 i so as to close the valve 5. B

reason of the spherical back end of the stem 6 being mounted in a spherical socket,

the valve 5 seats itself evenly and completely. By reason of the spring 22 being weaker than the spring17, the forward movement of the stem 6 and its rigidly connected parts in relation to the pivot 15 is much greater than is the movement of the sleeve 9 in relation to the stem. The valve 5 being closed, the parts are all in their original. positions as shown.

While the valve 5 is in a closed position,

there may develop abnormal conditions of high. temperature which will cause a gas pressure in thepassage 2 tending to become excessive and greater than the pressure in thepassage 3. In such a case, the high'gas pressure,

permit of the gas pressure olpening the valve. Thus the valve 5 operates not merely as a check valve between the passages 2 and 3, but also as a safety valve for the passage 2 and its connected still.

As an intermittently heated ammonia still begins to cool down, after the termination of each heating period, the weak liquor in the still becomes more. and more absorbent of any ammonia gas in contact with it. Consequently with such cooling down, the gas in the passage 2 begins to be re-absorbed and the pressure of the unabsorbed gas remaining in the passage 2 begins to fall. Under these conditions, if the valve were only an ordinary spring pressed check valve, it would close quite slowly and during its slow closing much gas would escape back from the condenser past the valve into the still, so as to greatly diminish the eliiciency of the machine. But

by causing the rod 4,3 to move downward so as to close and ldtk the valve 5 simultaneously with the termination of the heating of the still, any such loss of efiiciency is prevented. On the other hand, by causing the rod 43 to moveupward so as to unlock the valve 5 simultaneously with the beginning of the heating of the still, the valve opens just as soon as is desirable and as quickly as would an ordinary check valve. It also is to be noted that, in looking the valve 5 in a closed position consequent upon the downward movement of the rod 43, after the sleeve 9- has movedthe ring 18 by means of the spring 17 sufiiciently to close the valve, the sleeve can and does still further compress the spring so as to insure an absolutely tight closing of the valve. But if the sleeve 9 were to act directly on the stem 6, either the valve 5 might not close at all owing to a deficient forward movement of the stem or else the valve and stem might become strained owing to an excessive forward movement of the stem;

and it would be exceedingly difficult to so adjust the parts as to cause an exact and proper closing of the valve.

A diaphragm, such as the diaphragm 27, is capable of only a slight central movement without injury from distortion. Accordingly the lever 10, with its multiplying effect, is interposed between the thimble 26 and the stem 6, in preference to employing a more direct connection between these two latter parts.

While the valve structure is operative in any position, yet it is preferable that the position shown in the drawings shall be maintained. For as so shown the contact surfaces of the seat 4 and the valve 5 are in "a vertical plane so that no scale or other foreign 'matter can lodge between them, but, if coming from the direction of the condenser, will drop into the pocket at the lower end of the passage 3. This pocket is so designed as to provide for any ordinary accumulations of scale consequent upon a long period of operation. Of course the part of the passage 3 below the top of that part ofthe casing 1 between the passage 2 and the lowest part of the passage 3 will fill up with saturated aqua ammonia with the valve structure in the position shown; but such a condition does not interfere with the operation of the valve 5 and in this part of the machine does no other harm.

It is obvious that the caps 20, 29 and 45 are so constructed and positioned that the parts within the casing 1 are readily accessible for adjustment or replacement.

WVhat we have invented and what we desire to have protected by Letters Patent is expressed in claims as follows:

We claim:

I 1. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage and a valve seat between them, a valve for closing said seat, a rigid member connected to said valve, a strong compression spring bearing from behind upon said member, operativethereon when compressed in a forward direction to close said valve under normal conditions of pressure in said inlet passage and when compressed in a back direction by said member permitting an absolute opening of said valve, forward means for compressingsaid spring in a forward direction, and a weak compression spring bearing from in front .upon said member.

I 2. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage and a valve seat between them, a valve for closing said seat, a rigid member connected to said valve, a strong compression spring bearing from behind upon said member, operative thereon when compressed in a forward direction to close said valve under normal conditions of pressure in said inlet passage and when compressed in a back direction by said member permitting an absolute opening of said valve, forward means for compressing said spring in a forward direction, means either for holding said forward means in a position where said spring is compressed in such forward directionor for releasing said for- "ward means, and a weak compression spring bearing from in front upon said member.

3. In combination a casing having an inletpassage, an outlet passage leading from the inlet passage and a valve seat between them, a valve for closing said seat, a stem on being moved forwardclosing said valve,

means supporting said stem and permitting its reciprocation, a ring secured to said stem, a strong compression spring bearing upon the back of said ring, forward means for compressing said spring in a forward direction, and a weak compression spring bearing upon the front of said ring.

l. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage and a valve seat between them, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a strong compression spring bearing upon the back of said ring, forward means for compressing said spring ina forward direction, means either for holding said forward means in a position where said spring is compressed in such forward directionor for releasing said froward means, and a weak compression spring bearing upon the front of said ring.

5. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage and a valve seat between them, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a strong compression spring bearing upon the back of said ring, a sleeve bearing upon the back of said spring, means for moving said sleeve forward, and a weak compression spring bearing upon the front of said ring.

'6. In combination a casing having an inlet passage, an outlet passage leading from V the inlet passage and a valve seat between them, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a strong compression spring bearing upon the back of said ring, a sleeve bearing upon the back of said spring, means for moving said sleeve forward and holding it in such forward position or for releasing it, and a weak compression spring bearing upon the front of said ring.

7. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and i an 'imperforate diaphragm forming a part of the wall of the casing, a valve for closing said seat, means between said valve and said diaphragm and separate from the diaphragm whereby a movement of the diaphragm inward moves the valve a greater distance forward to close it, and means separate from and outside of said diaphragm for moving it inward and then for-releasing it.

8. In combination a casing having an inlet" passage ,'an* outlet passage leading from theinlet passage, a valve seat between themand a flexible diaphragm forming part of the wall of the casing, a valve forclosin said seat, means connecting said valve and said diaphragm whereby a movement of the diaphragm inward moves the valve a greater distance forward to close it, a thrusting member bearing upon the outside of said diaphragm and having an outer inclined face, means supporting said member and permitting its reciprocation, a rod having an inclined lateral face in contact with and parallel with the face of said member, and means supporting said rod and permitting its reciprocation.

9. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a rigid member connected to said valve, a compression spring bearing from behind upon said member, operative thereon when compressed in a forward direction to close said valve under normal conditions of pressure in said inlet passage and when compressed in a back direction by said member permitting an absolute opening of said valve, means connecting said spring and said diaphragm whereby a movement of the diaphragm inward compresses said spring a greater distance forward, and means for moving said diaphragm inward and then for releasing it.

10. In combination, a casing having an inlet passage, an outlet passage leading from th inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a rigid member connected to said valve, a compression spring bearing from behind upon said member, operative thereon when compressed in a forward direction to close said valve under normal conditions of pressure in said inlet passag and when compressed in a back direction by said member permitting an absolute opening of said valve, means connecting said spring and said diaphragm whereby a movement of the diaphragm inward compresses said spring a greater distance forward, a thrusting member bearingupon the outside of said diaphragm and having an outer inclined face, means supportingsaid'thrusting member and permitting its reciprocation, a rod having an inclined lateral face in contact with and parallel with the face of said thrusting member, and means supporting said rod and permitting its reciprocation.

11.'In combination a casing having an inlet passage, an outlet passage leading from'the inlet passage, a valve seat between them and a flexible diaphragm forming part ofthe wallof-thecasing, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a compression spring bearing upon the back of said ring, means connecting said spring and said diaphragm whereby a movement of the diaphragm inward compresses said spring a greater distance forward, and means for moving said diaphragm inward and then for releasing it.

12. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a compression spring bearing upon the back of said ring, means connecting said spring and said diaphragm whereby a movement of the diaphragm inward compresses said spring a greater distance forward, a thrusting member bearing upon the outside of said diaphragm and having an outer inclined face, means supporting said member and permitting its reciprocation, a rod having an inclined lateral face in contact with and parallel with the face of said member, and means supporting said rod and permitting its reciprocation.

13. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a compression spring bearing upon the back of said ring, a sleeve bearing upon the back of said spring, means connecting said sleeve and said diaphragm whereby a movement of the diaphragm inward moves the sleeve a greater distance forward, and means for moving said diaphragm inward and then for releasing it.

14. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a compression spring bearing upon the back of said ring, a sleeve bearing upon the back of said spring, means connecting said sleeve and said diaphragm whereby a movement of the diaphragm inward moves the sleeve a greater distance forward, a thrusting member bearing upon 1 the outside of said diaphragm and having an outer inclined face, means supporting said member and permitting its reciprocation, a rod having an inclined lateral face in contact with and parallel with the face of said member, and means supporting said rod and permitting its reciprocation.

15. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a rigid member connected to said valve, a strong compression spring bearing from behind upon said member, operative thereon when compressed in a forward direction to close said valve under normal conditions of pressure in said inlet passage and when compressed in a back direction by said member permitting an absolute opening of said valve, a weak compression spring bearing from in front upon said member, means connecting said strong spring and said diaphragm whereby a movement of the diaphragm inward compresses said strong spring a greater dis tance forward, and means for moving said diaphragm inward and then for releasing it.

16. In combinatior a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a rigid member connected to said valve, a strong compression spring bearing from behind upon said member, operative thereon when compressed in a forward direction to close said valve under normal conditions of pressure in said inlet passage and when compressed in a back direction by said member permitting an absolute opening of said valve, a weak compression spring bearing fromin front upon said member, means connecting said strong spring and said diaphragm whereby a movement of the diaphragm inward compresses said strong spring' a greater distance forward, a thrusting member bearing upon the outside of said diaphragm and having an outer inclined face, means supporting said thrusting member and permitting its reciprocation, a rod having an inclined lateral face in contact with and parallel with the face of said thrusting member, and means supporting said rod and permittingits reciprocation.

17 In combination a casinghaving an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said valve and permitting its reciprocatlon, a ring secured, to said stem,- a StBQHg compression spring bearing upon the back of said ring, a weak compression spring bearing upon the front of said ring, means connecting said strong spring and said diaphragm whereby a movement of the diaphragm inward compresses said strong spring a greater distance forward, and means for moving said diaphragm inward and then for releasing it.

18. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a strong compression spring bearing upon the back of said ring, a weak compression spring bearing upon the front of said ring, means connecting said strong spring and said diaphragm whereby a movement of the dia phragm inward compresses said strong spring a greater distance forward, a thrusting member bearing upon the outside of said diaphragm and having an outer inclined face, means supporting said member and permitting its reciprocation, a rod having an inclined lateral face in contact with and parallel with the face of said member, and means supporting said rod and permitting its reciprocation.

19. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valve for closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem a strong compression spring bearing upon the back of said ring, a sleeve bearing upon the back of said spring, a weak compression spring bearing upon the front of said ring, means connecting said sleeve and said diaphragm whereby a movement of the diaphragm inward moves the sleeve a greater distance forward, and means for moving said diaphragm inward and then for releasing it.

20. In combination a casing having an inlet passage, an outlet passage leading from the inlet passage, a valve seat between them and a flexible diaphragm forming part of the wall of the casing, a valvefor closing said seat, a stem on being moved forward closing said valve, means supporting said stem and permitting its reciprocation, a ring secured to said stem, a strong compression spring bearing upon the back of said ring, a sleeve bearing upon the back of said spring, a weak compression spring bearing upon the front of said ring, means connecting said sleeve and said diaphragm whereby a movement of the diaphragm inward moves the sleeve a greater distance forward, a thrusting member bearing upon the outside of said diaphragm and having an outer inclined face, means supporting said member and permitting its reciprocation, a rod having an inclined lateral face in contact with and parallel with the face of said member, and means supporting said rod and permitting its reciprocation.

GEORGE P. CARROLL. FRANK N. ROEHRICH. Witnesses:

JOHN E. PRAGER, A. WORDEN GIBBS.

Copies 01' this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0." 

